春末东海北部冷涡区环境特征及藻华成因探讨  

Environmental characteristics and phytoplankton bloom mechanisms in the cold eddy of northern East China Sea in late spring

作　　者：赵宇航 韦钦胜 辛明 谢琳萍 孙霞 王保栋 ZHAO Yu-hang;WEI Qin-sheng;XIN Ming;XIE Lin-ping;SUN Xia;WANG Bao-dong(Key Laboratory of Marine Eco-Environmental Science and Technology,First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,China;Laboratory for Marine Ecology and Environmental Science,Qingdao Pilot National Laboratory for Marine Science and Technology,Qingdao 266237,China)

机构地区：[1]自然资源部第一海洋研究所,海洋生态环境科学与技术重点实验室,山东青岛266061 [2]青岛海洋科学与技术试点国家实验室,海洋生态与环境科学功能实验室,山东青岛266237

出　　处：《中国环境科学》2023年第3期1349-1359,共11页China Environmental Science

基　　金：国家自然科学基金资助项目(41876085,42149902);中央级公益性科研院所基本科研业务费资助专项(GY0220S3);青岛海洋科学与技术试点国家实验室海洋生态与环境科学功能实验室开放基金资助项目(LMEES201808)。

摘　　要：基于2019年春末所获取的东海调查资料,通过分析温度、盐度、营养盐和叶绿素a(Chl-a)等理化参数的分布特征和空间格局,重点对东海北部冷涡区水文环境特征、营养盐动力过程及藻华发生机制进行了探讨.研究表明:济州岛西南海域的低温区清晰显示了春末东海北部冷涡的位置,且冷涡边缘锋面区冷水的抬升指示了上升流的存在.冷涡区的营养盐来源于冬季南下的黄海西部沿岸流的水平输运,冷涡边界锋区的上升流在一定程度上控制着营养盐的垂向输送.春末济州岛西南的Chl-a高值区(最高Chl-a含量为5.69μg/dm^(3))预示了藻华的发生,其与东海北部冷涡和营养盐高值区位置总体相吻合.较高的营养盐水平、良好的光照和增强的水体稳定度是春末东海北部冷涡区藻华形成的有利因素,同时该冷涡与南部高温、高盐水交汇形成的西北-东南向锋面对Chl-a高值区的空间格局与位置也具有重要影响.济州岛西南海域水体浊度较低,满足浮游植物生长所需光照条件所能达到的垂向深度较大,导致冷涡藻华区存在次表层Chl-a高值.该研究为进一步深入认识东海北部初级生产过程的调控机制和开展区域生态系统动力学研究等提供了重要科学依据.Based on the survey data obtained in the East China Sea(ECS)in the late spring of 2019,the distribution characteristics and spatial patterns of physical and chemical variables,including temperature,salinity,nutrients and chlorophyll a(Chl-a),were analyzed,and the hydrological environment characteristics,nutrients dynamic processes and phytoplankton bloom mechanisms in the cold eddy of the northern ECS were discussed.The low-temperature zone southwest of Cheju Island clearly showed the location of cold eddy in late spring,and the uplift of cold waters in the boundary area of this eddy indicated the presence of upwelling.The southward horizontal transport of the Yellow Sea western coastal current provided a source of nutrients for the cold eddy-dominated area,while the upwelling near the boundary of cold eddy controlled the vertical transport of nutrients to a certain extent.The high-Chl-a zone(with the highest Chl-a value of 5.69μg/dm^(3))southwest of Cheju Island implied the phytoplankton blooms in late spring,which generally coincided with the location of cold eddy and high-nutrient zone in the northern ECS.Relatively high nutrient levels,good light conditions,and enhanced water-column stability were favorable for the formation of phytoplankton blooms in the cold eddy of the northern ECS.Its suggested that the northwest-southeast front(formed by the confluence of the cold eddy and the southern high-temperature saline water mass)had an essential impact on the spatial pattern and location of the high-Chl-a zone.The relatively low turbidity in the region southwest of Cheju Island increased the vertical depth that could meet the light conditions required for phytoplankton growth,leading to a subsurface Chl-a maximum within the phytoplankton bloom area in the cold eddy of northern ECS.This study provided an essential scientific basis for further understanding the controlling mechanisms of primary production processes in the northern ECS and conducting regional ecosystem dynamics research.

关 键 词：东海北部冷涡 营养盐 藻华 东海 

分 类 号：X55[环境科学与工程—环境工程]